Whatever you decide to get you should get the highest level avail. I spent $2500 through CNA 6 months ago and have already used it to the tune of $900 to fix a leaking gasket. I have $100 deductible. They're great to deal with and the largest in the country. No muss, no fuss. However, having said that. Getting he warranty through BMW will allow you access to their bumper to bumper warranty just like buying a new bimmer comes with. The downside is that it is very expensive (like $2k) and its only good for a year.